Prevention of the deposition of slag in furnaces.



R. GRABOWSKY.

THE DEPOSITION 0F SLAG IN FURNACES. uczmou FILED APR.3.1915.

PREVENTIONHOF Patented July 20, 1915.

ROBERT GRAIBOWSKY, 0E HANOVER, GERMANY.

PREVENTION OF THE DEPOSITION OF SLAG IN FURNACES.

for quite small charges on the grate, it has been proposed already to replace the side walls by the walls of single water chambers. It isalso known in boilers having separate heating, to embed in the side Walls of the grate, pipes arranged like grate'bars but of round section, filled with water and connected to the interior of the boiler.-

As distinguished from the above, the present invention consists in using water-cooled pipes which have the wedge-shaped external section already known as applied to grate bars, the heads of these'being arranged to 7 project beyond the wall material which lies protected in the spaces between the pipes.

By the use of such wedge-shaped hollow bars like grate bars, a much better degree of protection and cooling of the wall material is attained than is possible with round-section cooling pipes. The broad and strong heads of the bars form a protecting surface parallel with the wall face, and the wall material cannot be attacked or damaged in the gaps between the grate-like bars. The whole, or almost the whole cross-section of the cooling passages lies however within the wall material.

The accompanying drawing shows an example of construction according to the invention:

Figure 1 is a vertical section through a furnace, suitable for instance for a steam boiler, and Fig. 2 is a corresponding horizontal section. Fig. 3 shows to a larger scale the section through some of the hollow bars.

The grate a which may, for example be a hollow water-cooled grate, is inclosed at the two sides by walls b and b and at the back Specification of Letters Patent. P t t d J l 2 1915 Application filed April 3, 1915. Serial No. 18,956. v

by a wall 6 of a combustion chamber. The

water-cooled bars 0 0 c are embedded in these walls, and have a wedge-shaped section as shown in Fig. 3. These bars are arranged like those of a grate at a certain distance from one another, and project at their expanded sides to some extent beyond the wall face on the side open to the grate, but

for the rest they lie embedded at their contracted sides in the interior of the wall as Fig. 3 clearly shows. The wall face nearest the grate therefore lies back from the faces of the hollow bars and is well protected. The combustible material consequently comes only into contact with the projecting faces of the bars a, 0 0 which are cooled by the water flowing through them. Slag cannot become deposited on these watercooled faces, and moreover the temperature is low enough inside the gaps between the Water-cooled bars to prevent deposition of slag on the wall faces in the gaps. It is of great importance also that damaging of the walls by the firemans tools is prevented because the tools can only come against the metal surfaces of the bars and cannot reach the receding wall faces in the narrow intervening gaps. If also the walls of the hollow bars. at the side directed toward the grate are made of increased thickness, as is indicated in Fig. 3, the protection becomes extremely reliable.

The invention is applicable to all kinds 0 furnaces, wherein walls of fireclay or the like are used for inclosing the grate area, no matter what kind of grate-bars may be employed. The grate may either be made up with ordinary massive bars which are stationary, or of moving set of bars, or also of hollow cooled grate-bars, as shown for example in the drawing. 'In the latter case the water supply for the hollow bars 0 c 0 may beconnected with the water system of therethrough. In the drawing an eizample is shown wherein the water used for cooling of hollow bars having a wedge-shaped the grate a also serves for the cooling of the bars 0 0 ,0 successively. v

What I claim is: In a furnace, a combustion chamber having side walls, combined with a plurality CI'QSSr-SQOtlQIl and embedded at their consignature in presence of two witnesses.

v ROBERT GRABOWSKY.

Witnesses: r

FRANZ O. KARNOWSKI, M. BURNE. 

